What I'm trying to do:
Arduino controlled automatic soda machine. The arduino is hooked up to a node.js web interface which sends commands via serial. I'd like to be able to hit a button on the website, and have it pour me a pop.
What I've learned:
This cannot be done with a pump, because apparently when you pump carbonated liquids, they go flat. So you're basically left going the CO2 route, like a Sodastream.
Assumptions/Givens:
Already figured out how to dispense the flavored syrup. Already purchased the CO2 tank, regulator, and ball lock+tubing. I am aware that machines like this actually exist now, but I'm trying to keep this small. The size of a CO2 tank and a few jugs of whatever soda syrup you desire should be all the space it takes up. By using a pump and solenoid valves to move the different syrups, it makes it very easy to add/remove syrup types, and you can get them in any form (bag, box, jug...)
What I'm thinking:
Pump soda syrup into your glass. Then, above your glass you have a pressurized bottle which holds a reservoir of plain soda water. This is dispensed via gravity into your glass by a valve on the bottom of the bottle which the arduino opens/closes. You could also have the arduino pump water into this for automatic refilling.
Questions: The CO2 injection into this bottle would probably have to be a manual process though? Or could it be done with a servo? How do you get an accurate measured amount into your glass? Where would you get a bottle like this? Are there high pressure valves that can be controlled electronically?
Does anyone have any other thoughts, or perhaps a different way entirely to go about this? I've posted all of my thoughts and the reasons behind them, but I'm in no way married to these methods. Thanks!
The gas can be controlled with a solenoid (which can be controlled by a arduino): gas for sale | eBay solenoid&_fscr=1
One suggestions I might have instead of the soda stream bottle (depending on how much you use it), find a home brew CO2 bottle, or a CO2 fire extinguisher (you'll need to get the trigger changed if you refill it, it'll leak over time). It's the same gas inside, it'll end up a lot cheaper.
I use it for welding, and the welders use gas solenoids to trigger the gas.
Hey, just thought I would open this thread back up even if you likely already have your answer.
sarink:
Questions: The CO2 injection into this bottle would probably have to be a manual process though? Or could it be done with a servo? How do you get an accurate measured amount into your glass? Where would you get a bottle like this? Are there high pressure valves that can be controlled electronically?
Ive been working on something similar for the past 4-5years, my home bar uses air(10 psi) to push drinks out of the tap(45in off ground). the reason I don't use windshield washer pumps, even though they are cheap, is because the sugar hardens and binds to the plastic and wears them out fast. If you plan on using solenoids, use plastic or pvc instead of brass for your soda water, this is because soda (H2CO3) reacts with the brass or copper, and strips the grime off (think polishing a penny), which will gives a weird taste.
The amount of carbonation is relative to the temperature of the water. To Carbonate the water to Coca-Cola Standards, you need 40psi for 20 degrees Celsius, and 18 psi for 4 degrees Celsius. To reduce this psi needed, sodastream uses a small nozzle (fast expansion) to create lots of turbulence which is proportional to amount of CO2 reacting with H2O. There is no cheap way to regulate the air via an arduino (unless you know something I dont), but I always thought about trying to macguiver a servo ontop a digital regulator to control it with a feedback loop.
Hi, While I am fairly comfortable with arduino, Im just now starting to look into compressors and solenoid systems for distributing coke/gingerale/tonic . Are there any good diagrams or systems out there that show how to do this?
I am a bit worried about blowing up the setup first time I try
I am working on something similar at the moment. I am new to the arduino world, and I was hoping you could send me some of the code for your system? I am having trouble scripting it.
